The present disclosure relates to a semiconductor unit capable of detecting, for example, a defect caused by misalignment from various defects produced in a manufacturing process for ICs (Integrated Circuits) or the like, and a test method using such a semiconductor unit.
During or after a manufacturing process for electronic components such as ICs, a judgment test to determine whether the electronic components are conforming items or defective items is performed. The ICs judged as defective items may be used for an improvement in yields by categorizing the defective ICs, based on, for example, causes of defects.
To improve yields, it is important to analyze causes of defects and clarify a step to be improved in the manufacturing process for ICs. Moreover, it is desirable to perform cause analysis of defects for a short time, thereby leading to a reduction in time necessary to improve yields.
Examples of the above-described defects include defects caused by misalignment (superposition misalignment) between layers. Moreover, some of defects caused by the misalignment may be produced not during the process but after the process (afterward). Therefore, it is desirable to execute a defect judgment test on all components after completion of the components.
An example of such a test technique may be a burn-in test. Moreover, in addition to the burn-in test, there is proposed a technique of detecting misalignment with use of a capacitor, based on a change in capacity of the capacitor (for example, refer to Japanese Unexamined Patent Application Publication No. 2001-118901).